FIELD: chemistry.
SUBSTANCE: invention relates to a method of preparing a zeolite, having elementary cell size in the range of 24.42 to 24.52 E; molar ratio of silica/alumina in mass in the range of 10 to 15; and surface area of 910 to 1020 m2/g, which includes: a) obtaining an initial zeolite with a faujasite structure, having silica/alumina ratio of 4.5 to 6.5 and alkali level lower than 1.5 wt %; b) steam tempering by treating said initial zeolite at temperature in the range of 550 to 750°C and partial steam pressure in the range of 5 to 50 vol% with respect to the total volume of the present gas over time, sufficient to obtain an intermediate zeolite with elementary cell size of 24.40 to 24.50 E; c) bringing the intermediate zeolite into contact with an acidified solution containing 4 to 9 mmol acid with pKa lower than 0 per gram zeolite and optionally an ammonium salt in conditions which enable to form a zeolite having elementary cell size of 24.42 to 24.52 E; silica/alumina ratio in the range of 10 to 15; and surface area of 910 to 1020 m2/g; and d) separating said zeolite. The invention also relates to methods of preparing a catalyst support composition, the catalyst itself, as well as a method of converting hydrocarbon material into materials with a lower boiling point.
EFFECT: high activity and selectivity with respect to heavy naphtha of faujasite-based catalysts.
8 cl, 1 tbl, 5 ex
